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1.
Artigo em Inglês | MEDLINE | ID: mdl-39170624

RESUMO

Peribiliary glands are complex lobular structures containing mucus and serous glands, distributed along the extrahepatic and intrahepatic bile ducts. In this report, we describe a case of intraductal papillary neoplasm of the bile duct suspected to be of peribiliary glands origin. The patient was an 80-year-old man who was referred to our hospital for a hepatic mass. On further examination, a 38 × 34 mm cystic lesion with papillary growth was found in S1/4. Because the lesion was extensively bordered by both hepatic ducts and the connection was unclear, it was difficult to determine the extent of hepatic resection. To confirm the location, a peroral cholangioscopy was performed. The connection with the cyst was detected in the right hepatic duct and a villous tumor mucosa protruded through the conduit lumen. Since we found that the lesion communicated with the right hepatic duct, a right hepatectomy was subsequently performed. The postoperative pathological diagnosis was an intraductal papillary neoplasm of the blie duct with associated invasive carcinoma. The postoperative course was good, and the patient experienced no recurrence.

2.
Phys Chem Chem Phys ; 26(24): 17205-17212, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38855902

RESUMO

This study investigated the structures of fragment ions derived from the quinoline (C9H7N) radical cation using ion-mobility spectrometry and mass spectrometry. Ion mobility and mass analysis revealed that C8H6˙+ is the primary dissociation product resulting from the loss of HCN during collision-induced dissociation of the quinoline radical cation. The reduced mobility (K0) of the C8H6˙+ fragment product in helium gas was measured over a range of reduced electric fields (E/N = 20.8-27.4 Td) at room temperature. The experimental K0 values indicated that C8H6˙+ is a mixture of phenylacetylene and pentalene radical cations. Furthermore, quantum chemical calculations revealed two potential energy surfaces delineating the loss of HCN from the quinoline radical cation to form phenylacetylene radical cations.

3.
J Biochem ; 176(2): 109-117, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38498909

RESUMO

Glycogen debranching enzyme is a single polypeptide with distinct catalytic sites for 4-α-glucanotransferase and amylo-α-1,6-glucosidase. To allow phosphorylase to degrade the inner tiers of highly branched glycogen, 4-α-glucanotransferase converts the phosphorylase-limit biantennary branch G-G-G-G-(G-G-G-G↔)G-G- (G: d-glucose, hyphens: α-1,4-linkages; double-headed arrow: α-1,6-linkage) into the G-G-G-G-(G↔)G-G- residue, which is then subjected to amylo-α-1,6-glucosidase to release the remaining G↔ residue. However, while the essential side-chain structure of the 4-α-glucanotransferase donor substrate has been determined to be the G-G-G-G↔ residue (Watanabe, Y., et al. (2008) J. Biochem.143, 435-440), its essential main-chain structure remains to be investigated. In this study, we probed the 4-α-glucanotransferase donor-binding region using novel fluorogenic dextrins Gm-(G4↔)G-Gn-F (F: 1-deoxy-1-[(2-pyridyl)amino]-d-glucitol) and maltohexaose (G6) as the donor and acceptor substrates, respectively. 4-α-Glucanotransferase exhibited maximum activity towards G4-(G4↔)G-F and G4-(G4↔)G-G-F, indicating that recognition of the G4-(G4↔)G-moiety was essential for full enzyme function. Notably, when the 4-α-glucanotransferase activity towards G4-(G4↔)G-G-F was taken as unity, those towards nonbranching dextrins were < 0.001. This indicated that the disproportionation activities towards maltooligosaccharides (Gm) are abnormal behaviours of 4-α-glucanotransferase. Notably, however, these activities have been traditionally measured to identify the 4-α-glucanotransferase mutations causing glycogen storage disease type III. This study provides a basis for more accurate identification.


Assuntos
Dextrinas , Sistema da Enzima Desramificadora do Glicogênio , Sistema da Enzima Desramificadora do Glicogênio/metabolismo , Sistema da Enzima Desramificadora do Glicogênio/química , Sistema da Enzima Desramificadora do Glicogênio/genética , Dextrinas/metabolismo , Dextrinas/química , Especificidade por Substrato
4.
Amino Acids ; 56(1): 14, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38340233

RESUMO

Glycogen phosphorylase (GP) is biologically active as a dimer of identical subunits, each activated by phosphorylation of the serine-14 residue. GP exists in three interconvertible forms, namely GPa (di-phosphorylated form), GPab (mono-phosphorylated form), and GPb (non-phosphorylated form); however, information on GPab remains scarce. Given the prevailing view that the two GP subunits collaboratively determine their catalytic characteristics, it is essential to conduct GPab characterization to gain a comprehensive understanding of glycogenolysis regulation. Thus, in the present study, we prepared rabbit muscle GPab from GPb, using phosphorylase kinase as the catalyst, and identified it using a nonradioactive phosphate-affinity gel electrophoresis method. Compared with the half-half GPa/GPb mixture, the as-prepared GPab showed a unique AMP-binding affinity. To further investigate the intersubunit communication in GP, its catalytic site was probed using pyridylaminated-maltohexaose (a maltooligosaccharide-based substrate comprising the essential dextrin structure for GP; abbreviated as PA-0) and a series of specifically modified PA-0 derivatives (substrate analogs lacking part of the essential dextrin structure). By comparing the initial reaction rates toward the PA-0 derivative (Vderivative) and PA-0 (VPA-0), we demonstrated that the Vderivative/VPA-0 ratio for GPab was significantly different from that for the half-half GPa/GPb mixture. This result indicates that the interaction between the two GP subunits significantly influences substrate recognition at the catalytic sites, thereby providing GPab its unique substrate recognition profile.


Assuntos
Dextrinas , Glicogênio Fosforilase , Animais , Coelhos , Domínio Catalítico , Glicogênio Fosforilase/metabolismo , Músculos/metabolismo , Comunicação
5.
Artigo em Inglês | MEDLINE | ID: mdl-37523000

RESUMO

Conventional ultrasonography (US) for biliary tract disease shows high time and spatial resolution. In addition, it is simple and minimally invasive, and is selected as a first-choice examination procedure for biliary tract disease. Currently, contrast-enhanced US (CEUS), which facilitates the more accurate assessment of lesion blood flow in comparison with color and power Doppler US, is performed using a second-generation ultrasonic contrast agent. Such agents are stable and provide a timeline for CEUS diagnosis. Gallbladder lesions are classified into three types: gallbladder biliary lesion (GBL), gallbladder polypoid lesion (GPL), and gallbladder wall thickening (GWT). Bile duct lesions can also be classified into three types: bile duct biliary lesion (BBL), bile duct polypoid lesion (BDPL), and bile duct wall thickening (BDWT). CEUS facilitates the differentiation of GBL/BBL from tumorous lesions based on the presence or absence of blood vessels. In the case of GPL, it is important to identify a vascular stalk attached to the lesion. In the case of GWT, the presence or absence of a non-contrast-enhanced area, the Rokitansky-Aschoff sinus, and continuity of a contrast-enhanced gallbladder wall layer are important for differentiation from gallbladder cancer. In the case of BDWT, it is useful to evaluate the contour of the contrast-enhanced medial layer of the bile duct wall for differentiating IgG4-related sclerosing cholangitis from primary sclerosing cholangitis. CEUS for ampullary carcinoma accurately reflects histopathological findings of the lesion. Evaluating blood flow in the lesion, continuity of the gallbladder wall, and contour of the bile duct wall via CEUS provides useful information for the diagnosis of biliary tract disease.

6.
Glycoconj J ; 39(3): 345-355, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35192094

RESUMO

Glycogen debranching enzyme (GDE) is bifunctional in that it exhibits both 4-α-glucanotransferase and amylo-α-1,6-glucosidase activity at two distinct catalytic sites. GDE converts the phosphorylase-limit biantennary branch [G-G-G-G-(G-G-G-G↔)G-G- residue, where G = D-glucose, hyphens represent α-1,4-glycosidic bonds, and the double-headed arrow represents an α-1,6-glycosidic bond] into a linear maltooligosyl residue, which is then subjected to phosphorylase, and glycogen degradation continues. The prevailing hypothesis regarding the glycogen debranching pathway was that 4-α-glucanotransferase converts the phosphorylase-limit biantennary branch into the G-G-G-G-G-G-G-(G↔)G-G- residue and amylo-α-1,6-glucosidase cleaves the remaining α-1,6-linked G residue. In the present study, we analyzed the substrate specificities of 4-α-glucanotransferase and amylo-α-1,6-glucosidase using fluorogenic biantennary dextrins such as G-G-G-G-(G-G-G-G↔)G-G-GPA (F4/4/2; where GPA = 1-deoxy-1-[(2-pyridyl)amino]-D-glucitol), G-(G-G-G-G↔)G-G-GPA (F1/4/2), and G-G-G-G-G-G-G-(G↔)G-G-GPA (F7/1/2). Contrary to the prevailing hypothesis, the main branch of F4/4/2 was an important donor substrate component of 4-α-glucanotransferase and did not serve as an acceptor substrate. However, when G-G-G-G-G-GPA was added to the mixture, it successfully accepted a maltotriosyl (G3-) residue from F4/4/2. In addition, amylo-α-1,6-glucosidase exhibited strong activity towards G-G-G-G-(G↔)G-G-GPA but weak activity towards F7/1/2. Furthermore, the debranching activity of GDE towards phosphorylase-limit glycogen substantially increased when methyl α-maltooligosides with lengths equal to or greater than that of methyl α-maltopentaoside (G5-OCH3) were added to the enzyme reaction mixture. Based on these results, we propose the following macroscopic debranching pathway: Via 4-α-glucanotransferase, the G3- residue of the donor branch is transferred to a long (n ≥ 5) linear Gn- residue linked to a different branching G residue.


Assuntos
Sistema da Enzima Desramificadora do Glicogênio , Glucose , Glicogênio/metabolismo , Sistema da Enzima Desramificadora do Glicogênio/química , Fígado/metabolismo , Especificidade por Substrato
7.
Org Biomol Chem ; 19(21): 4775-4782, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33978050

RESUMO

Many hydrogen abstraction reactions on sp3 carbons with oxyradicals take place site-selectively (regioselectively). To investigate this selectivity, ab initio and density functional theory (DFT) calculations were carried out using cyclopentanone and SO4-˙ as the substrate and oxyradical, respectively. At the ωB97XD/6-311+G(d,p) level, the energy barriers for the forward process (ΔE1‡) of both α- and ß-hydrogen abstraction were predicted to be 54.6 and 50.9 kJ mol-1, respectively. Consideration of solvent effects (acetonitrile) decreased these energy barriers to 33.2 and 26.1 kJ mol-1, respectively. These calculation outcomes suggested that ß-hydrogen abstraction would be favourable, which supports experimental findings (i.e. ß-selective abstraction). At the ωB97XD level, investigations into hydrogen abstraction from cyclohexanone with SO4-˙ confirmed the regioselectivity observed experimentally. Hydrogen abstractions from 2-propylpyridine and 3-methyl-1-butanol using SO4-˙, which are unknown reactions, were also calculated using the DFT method, and the predicted regioselectivity was consistent with that in the known reactions using tetrabutylammonium decatungstate (TBADT). In addition, regioselectivities in unexplored hydrogen abstractions of cyclopentanone by several oxyradicals were predicted. Natural bond orbital (NBO) analysis carried out at the ωB97XD level indicated that the transferred hydrogen atom is partially positively charged when abstracted by an oxyradical. Interestingly, hydrogens bonded to the most positively charged carbon in the substrate were predominantly abstracted by oxyradicals in practice, which should be a simple compass for predicting regioselectivity in the functionalisation of C(sp3)-H bonds with oxyradicals.

8.
Chemistry ; 27(37): 9529-9534, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-33851767

RESUMO

The redox-neutral tetrafluoroethylation of alkynes with 1,1,2,2-tetrafluroroethanesulfonic acid (TFESA) and azobis(isobutyronitrile) (AIBN) proceeds via the formation of vinyl tetrafluoroethanesulfonates followed by a radical tetrafluoroethylation. Experimental and theoretical results support an intermolecular reaction.


Assuntos
Alcinos , Ácidos Sulfônicos , Acetofenonas , Hidrocarbonetos Fluorados , Oxirredução
9.
Glycoconj J ; 37(6): 667-679, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33201379

RESUMO

Glycogen debranching enzyme (GDE), together with glycogen phosphorylase (GP), is responsible for the complete degradation of glycogen. GDE has distinct catalytic sites for 4-α-glucanotransferase and amylo-α-1,6-glucosidase. For the GDE sensitive assay, we previously developed the GP limit fluorogenic branched dextrin Glcα1-4Glcα1-4Glcα1-4Glcα1-4(Glcα1-4Glcα1-4Glcα1-4Glcα1-6)Glcα1-4Glcα1-4Glcα1-4GlcPA (B4/84, where Glc = D-glucose and GlcPA = 1-deoxy-1-[(2-pyridyl)amino]-D-glucitol). However, B4/84 is not widely available because of difficulties in its chemical synthesis and positional-isomer separation (0.33% yield by α-1,6-coupling of maltotetraose with Glc7-GlcPA). In this study, we attempted to develop an efficient method for the preparation of Glcα1-4Glcα1-4Glcα1-4Glcα1-4(Glcα1-4Glcα1-4Glcα1-4Glcα1-6)Glcα1-4Glcα1-4GlcPA (B3/74), which was designed to have the minimum essential dextrin structure for GDE. First, Glcα1-6Glcα1-4Glcα1-4GlcPA (B3/31) was prepared from commercially available Glcα1-6Glcα1-4Glcα1-4Glc. Using α-cyclodextrin as a donor substrate, cyclodextrin glucanotransferase elongated both the main and side branches on B3/31, while all the glycosidic bonds in B3/31 were left intact. After exhaustive digestion with GP, B3/74 was obtained from B3/31 with 16% yield, a value that is 48-fold greater than that previously reported for B4/84. GDE 4-α-glucanotransferase exhibited high activity toward both B3/74 and B4/84. In addition, we studied the efficient conversion of B3/74 into Glcα1-4Glcα1-4Glcα1-4Glcα1-4(Glcα1-6)Glcα1-4Glcα1-4GlcPA (B3/71), which has the best dextrin structure for the GDE amylo-α-1,6-glucosidase.


Assuntos
Dextrinas/química , Sistema da Enzima Desramificadora do Glicogênio/química , Glicogênio/genética , Fígado/metabolismo , Sítios de Ligação/genética , Cromatografia Líquida de Alta Pressão , Corantes Fluorescentes/química , Glucosiltransferases/química , Glicogênio/química , Sistema da Enzima Desramificadora do Glicogênio/genética , Glicogênio Fosforilase/química , Glicogênio Fosforilase/genética , Humanos , Oligossacarídeos/química
10.
Endoscopy ; 52(11): 978-985, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32583394

RESUMO

BACKGROUND: Detailed histological evaluation is important in the diagnosis of autoimmune pancreatitis (AIP). However, it remains challenging to obtain adequate tissue from the pancreas. Recently, several reports have suggested the usefulness of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) using the new "core" needles for acquiring pancreatic tissue. We aimed to investigate the usefulness of EUS-FNB for diagnosing AIP with one such needle, a 22-gauge Franseen needle. METHODS: Patients who met the imaging diagnostic criteria for AIP based on the International Consensus Diagnostic Criteria (ICDC) were enrolled in the study. All patients underwent EUS-FNB with a 22-gauge Franseen needle. Histological findings were evaluated based on the ICDC, and the detection rates of level 1 and level 1 or 2 histology were calculated. RESULTS: 56 patients from 11 different institutions were enrolled in the final analysis (55 suspected to have type 1 AIP and one with type 2 AIP). Lymphoplasmacytic infiltration, obliterative phlebitis, storiform fibrosis, and > 10 IgG4-positive cells per high-power field were detected in 55 (100 %), 24 (43.6 %), 40 (72.7 %), and 36 (65.5 %) of the 55 patients, respectively. The detection rates of level 1 and level 1 or 2 histology for AIP were 58.2 % (95 % confidence interval [CI] 44.1 % - 71.3 %) and 92.7 % (95 %CI 82.4 % - 98.0 %), respectively, which were apparently higher than our historical results (7.9 % [95 %CI 1.7 % - 21.4 %] and 62.2 % [95 %CI 46.5 % - 76.2 %], respectively) using a conventional needle. CONCLUSIONS: EUS-FNB with a 22-gauge Franseen needle demonstrated favorable detection rates which would be clinically beneficial for the histological diagnosis of AIP.


Assuntos
Doenças Autoimunes , Pancreatite Autoimune , Pancreatite , Doenças Autoimunes/diagnóstico por imagem , Biópsia por Agulha Fina , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Agulhas , Pancreatite/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia de Intervenção
11.
J Org Chem ; 85(9): 6137-6142, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32227846

RESUMO

The decyanation of secondary aliphatic nitriles and the 2-fold decyanation of malononitriles leading to alkanes in the presence of 1,3-dimethylimidazol-2-ylidene borane (diMeImd-BH3) are reported. These reactions proceed via a radical mechanism that involves the addition of a borane radical to the nitrile to form an iminyl radical, followed by cleavage of a carbon-carbon bond. Theoretical calculations suggest that the ß-cleavage of these iminyl radicals, which affords NHC-BH2CN and the corresponding alkyl radicals, is the rate-determining step in this reaction.

12.
Dig Endosc ; 31(4): 439-447, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30714216

RESUMO

OBJECTIVES: The time to recurrent biliary obstruction (TRBO) of unresectable distal malignant biliary obstruction is generally thought to be longer when a self-expandable metal stent (SEMS) with a thicker inner diameter is used for drainage, but the dependence on the inner diameter using a fully covered SEMS (FCSEMS) is uncertain. The objective of this multicenter prospective study was to compare TRBO and adverse events, such as cholecystitis and pancreatitis, in treatment of patients with unresectable malignant biliary obstruction using 8- and 10-mm diameter FCSEMS. METHODS: Eighteen tertiary-care centers participated in the study. Patients were allocated to the 8- and 10-mm diameter groups. TRBO, non-inferiority of the 8-mm FCSEMS, overall survival time, frequency and type of adverse events, and non-recurrent biliary obstruction (RBO) rate at the time of death were compared between the two groups. RESULTS: Median TRBO did not differ significantly between the 8-mm (n = 102) and 10-mm (n = 100) groups (275 vs 293 days, P = 0.971). The hazard ratio of the 8- to 10-mm groups was 0.90 (80% confidence interval, 0.77-1.04; upper limit lower than the acceptable hazard ratio [1.33] of the null hypothesis). Based on these findings, the 8-mm diameter stent was determined to be non-inferior to the 10-mm diameter stent. Survival time, incidence of adverse events and non-RBO rate at the time of death did not differ significantly between the two groups. CONCLUSIONS: Time to RBO with an 8-mm diameter FCSEMS was non-inferior to that with a 10-mm diameter FCSEMS. This finding is important for development of future SEMS.


Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Colestase/cirurgia , Stents Metálicos Autoexpansíveis/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/mortalidade , Colecistite/etiologia , Colecistite/mortalidade , Colestase/mortalidade , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/etiologia , Pancreatite/mortalidade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Estudos Prospectivos
13.
Oncology ; 96(1): 1-7, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30368509

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of alternate-day administration of S-1 as second-line chemotherapy for unresectable pancreatic cancer in a multicenter, randomized, phase II study. METHODS: Patients with histologically proven, unresectable pancreatic cancer treated with chemotherapy not including S-1 as first-line therapy were randomly assigned to receive either daily or alternate-day treatment with S-1. The primary end point was overall survival (OS), and the secondary end points were progression-free survival (PFS), time to treatment failure (TTF), response rate, and adverse events. RESULTS: A total of 77 patients were enrolled, of which 75 were included in the final analysis. The median OS was 4.5 months in the daily group and 4.4 months in the alternate-day group (HR 1.178; 95% CI 0.741-1.875), with no significance in PFS and TTF. The response rate was 2.8% in the daily group and 0% in the alternate-day group. Grade 3 or higher adverse events occurred with significantly higher incidence in the daily group (47.2 vs. 25.6%, p = 0.044). CONCLUSION: As a second-line chemotherapy for unresectable pancreatic cancer, although the efficacy in both groups was comparable and we can expect fewer toxicities with alternate-day administration of S-1, the noninferiority of alternate-day treatment to daily treatment with S-1 was not verified.


Assuntos
Ácido Oxônico/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Tegafur/uso terapêutico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Esquema de Medicação , Combinação de Medicamentos , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Ácido Oxônico/administração & dosagem , Ácido Oxônico/efeitos adversos , Neoplasias Pancreáticas/mortalidade , Retratamento , Tegafur/administração & dosagem , Tegafur/efeitos adversos , Resultado do Tratamento
14.
Intern Med ; 58(7): 1017-1022, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30568124

RESUMO

We herein report a case of a 75-year-old woman who presented with a low-grade fever, repeated cold-induced urticaria, and painful leg edemas with neutrocytosis. Because her mother also had cold-induced urticaria and her skin lesions histologically showed neutrophilic dermatitis, we suspected that she had familial cold autoinflammatory syndrome, a subtype of cryopyrin-associated periodic syndromes. Sequencing of the NLRP3 and MEFV genes revealed that she carried both the p.A439V missense mutation and p.E148Q homozygous mutation, which is commonly detected in familial Mediterranean fever patients. The administration of colchicine reduced the frequency and severity of her skin rash and leg edema.


Assuntos
Síndromes Periódicas Associadas à Criopirina/diagnóstico , DNA/genética , Mutação , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Pirina/genética , Idoso , Biópsia , Síndromes Periódicas Associadas à Criopirina/genética , Análise Mutacional de DNA , Febre Familiar do Mediterrâneo/genética , Feminino , Homozigoto , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pirina/metabolismo , Doenças Raras
15.
Nihon Shokakibyo Gakkai Zasshi ; 115(11): 985-995, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30416160

RESUMO

A woman in her 70s presented to our hospital with epigastric pain, back pain, and weight loss. Esophagogastroduodenoscopy was performed, and numerous protuberances, which were suspected to be submucosal tumors, were found at the gastric corpus. The patient was diagnosed with gastric tuberculosis based on the biopsy results of these protuberances. Histopathological analysis demonstrated non-caseating epithelioid granuloma. A positive culture for Mycobacterium tuberculosis was also obtained on gastric juice analysis and confirmed using polymerase chain reaction assay. In the rapidly aging population in Japan, our findings emphasize on the importance of differentiating gastrointestinal tuberculosis, including gastric tuberculosis, from other diseases. This case may provide information about the development of gastric tuberculosis.


Assuntos
Mycobacterium tuberculosis/crescimento & desenvolvimento , Tuberculose Gastrointestinal/diagnóstico , Idoso , Antituberculosos , Feminino , Humanos , Japão , Estômago , Tuberculose Gastrointestinal/microbiologia
16.
Acc Chem Res ; 51(9): 2023-2035, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30137961

RESUMO

1,4-Hydrogen transfer from the 1-hydroxyallyl radical to give the enoxyl (α-keto) radical is an exothermic process with a high activation energy based on DFT calculations. The lack of experimental examples of such 1,4-H shift reactions lies in the difficulty of generating the 1-hydroxyallyl radical. We have shown that radical carbonylation of alkenyl radicals with CO followed by nucleophilic trapping of the carbonyl portion of the resulting radical by amines gives rise to 1-amino-substituted 1-hydroxyallyl radicals in situ. At the outset of this chemistry, we examined intramolecular trapping reactions via radical carbonylation of alkynylamines mediated by tributyltin hydride. Consequently, α-methylene lactams were obtained, for which the initially formed 1-amino-substituted 1-hydroxyallyl radical underwent a 1,4-H shift followed by subsequent ß-scission, which led to the expulsion of a tributyltin radical. A competing pathway of the 1,4-H shift of 1-amino-substituted 1-hydroxyallyl radicals involving hydrogen abstraction was observed, which led to the formation of α-stannylmethylene lactams as a major byproduct. However, in contrast, when intermolecular trapping of α-ketenyl radicals by amines was carried out, the 1,4-H shift from the 1-amino-substituted 1-hydroxyallyl radical became the major pathway, which gave good yields of α,ß-unsaturated amides. Thus, we were able to develop three-component reactions comprising terminal alkynes, CO, and amines that led to α,ß-unsaturated amides via the 1,4-H shift reaction. DFT calculations support the observation that the 1,4-H shift is more facile when 1-hydroxyallyl radicals have both 1-amino and 3-tin substituents. The choice of substituents on the amine nitrogen is also important, since N-C bond cleavage via an SH2-type reaction can become a competing pathway. Such an unusual SH2-type reaction at the amine nitrogen is favored when the leaving alkyl radicals are stable, such as PhC(•)H(CH3) and t-Bu•. Interestingly, even nucleophilic attack of tertiary amines onto α-ketenyl radicals causes cleavage of the C-N bond. For this reaction, DFT calculations predict an indirect homolytic substitution mechanism involving expulsion of alkyl radicals through the zwitterionic radical intermediate arising from nucleophilic amine addition onto the α-ketenyl radical. In contrast, the carbonylation of aryl radicals, generated from aryl iodides, in the presence of amines gave aromatic carboxylic amides in good yields. It is proposed that radical anions originating from acyl radicals and amines undergo electron transfer to aryl iodides to give aminocarbonylation products.

17.
Org Biomol Chem ; 16(24): 4517-4526, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29873381

RESUMO

Trifluoromethylation using Umemoto's reagent is an important transformation that allows the preparation of compounds bearing trifluoromethyl groups. To investigate the mechanism of this reaction, ab initio and density functional theory (DFT) calculations were carried out using pyrrole, aniline, sodium acetylacetonate, and sodium methyl acetoacetate as nucleophiles. At the highest level of theory examined (i.e., CCSD(T)/6-311+G(d,p)//M06-2X/6-311+G(d,p)), the energy barriers for the forward process (ΔE‡1) of both the backside and frontside attack of pyrrole on a model Umemoto reagent (i.e., S-(trifluoromethyl)dimethylsulfonium, CF3DMS) were predicted to be 135.9 and 192.3 kJ mol-1, respectively, while values of 131.9 and 188.2 kJ mol-1 were obtained at the MP2/6-311+G(d,p)//M06-2X/6-31+G(d,p) level. These outcomes suggest that the reaction proceeds via the backside mechanism. Using the MP2 method, the investigation of the trifluoromethylation of pyrrole and sodium acetoacetate with the sulfonium moiety of Umemoto's reagent, S-(trifluoromethyl)dibenzothionium, revealed that this reaction would also occur through the backside mechanism, thereby indicating that this pathway remains feasible despite solvent effects. Finally, computational investigations revealed that the simple single-electron transfer mechanism, which should occur between Umemoto's reagent and nucleophiles, did not take place during this reaction.

18.
J Gastroenterol Hepatol ; 33(1): 320-328, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28872701

RESUMO

BACKGROUND AND AIM: The aim of this study is to elucidate the natural history of pancreatic cystic lesions (PCLs), including branch duct-type intraductal papillary mucinous neoplasm (BD-IPMN), via midterm follow-up analysis of a multicenter prospective observational study (NSPINAL study). METHODS: From July 2011 to October 2016, 881 patients with PCLs were enrolled in NSPINAL study, and 664 patients with > 12 months of follow up were analyzed. Every patient was asymptomatic, and endoscopic ultrasound was performed at the initial diagnosis to exclude high-risk individuals. Follow up included endoscopic ultrasound, computed tomography, or magnetic resonance imaging at least once a year. Serial morphological changes and the pancreatic cancer (PC) incidence, including malignant progression of PCLs, were evaluated. RESULTS: The 664 patients (358 men) were followed for a median of 33.5 months (interquartile range 29). The cyst and main pancreatic duct sizes were 16.6 ± 9.3 and 2.3 ± 1.0 mm, respectively. Morphologically, 518 cases were multilocular, 137 were unilocular, and 9 had a honeycomb pattern; 269 cases involved multifocal lesions. Ninety-six patients (14.5%) showed worsening progression on imaging. There were two resectable and four unresectable cases of pancreatic ductal adenocarcinoma and three cases of malignant BD-IPMN. The 3-year risk of developing PC was 1.2%. The standardized incidence ratio for PC among PCLs was 10.0 (95% confidence interval 3.5-16.5), and the standardized incidence ratio among BD-IPMN was 16.6 (95% confidence interval 5.1-28.1). Multivariate analysis showed that development of symptoms and worsening progression were significant predictors of PC. CONCLUSIONS: Malignant progression of PCLs, including PC development, is not uncommon. Patients with PCLs should be carefully monitored to detect pancreatic ductal adenocarcinoma at early stages.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/etiologia , Cisto Pancreático/complicações , Cisto Pancreático/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/etiologia , Medição de Risco , Idoso , Carcinoma Ductal Pancreático/patologia , Diagnóstico por Imagem , Progressão da Doença , Detecção Precoce de Câncer , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cisto Pancreático/patologia , Neoplasias Pancreáticas/patologia , Estudos Prospectivos , Risco , Fatores de Tempo
19.
Nihon Shokakibyo Gakkai Zasshi ; 114(7): 1277-1284, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28679984

RESUMO

A 67-year-old male patient presented with an irregular mass involving the pancreatic body and tail with multiple liver/lymph node metastases. A biopsy indicated the presence of a poorly differentiated adenocarcinoma. Fever and increased white blood cell count, C-reactive protein levels, and granulocyte-colony stimulating factor (G-CSF) levels led to the diagnose of G-CSF-producing pancreatic cancer. The patient did not respond to FOLFIRINOX therapy (leucovorin, fluorouracil, irinotecan, and oxaliplatin), but nab-paclitaxel plus gemcitabine treatment was effective, resulting in tumor shrinkage and reduced G-CSF levels. After the fifth course of this therapy, exacerbation was noted, and the patient died of primary cancer 6 months after initiating the therapy. Here we report the case of this patient with G-CSF-producing pancreatic cancer who responded to chemotherapy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/biossíntese , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/metabolismo , Idoso , Albuminas/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Evolução Fatal , Humanos , Masculino , Paclitaxel/administração & dosagem , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Gencitabina
20.
World J Gastrointest Endosc ; 9(4): 189-195, 2017 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-28465786

RESUMO

AIM: To determine the risk factors of severe post endoscopic retrograde cholangiopancreatography pancreatitis (sPEP) and clarify the indication of prophylactic treatments. METHODS: At our hospital, endoscopic retrograde cholangiopancreatography (ERCP) was performed on 1507 patients from May 2012 to December 2015. Of these patients, we enrolled all 121 patients that were diagnosed with post endoscopic retrograde PEP. Fourteen of 121 patients diagnosed as sPEP were analyzed. RESULTS: Forty-one patients had contrast media remaining in the pancreatic duct after completion of ERCP. Seventy-one patients had abdominal pain within three hours after ERCP. These were significant differences for sPEP (P < 0.05). The median of Body mass index, the median time for ERCP, the median serum amylase level of the next day, past histories including drinking and smoking, past history of pancreatitis, sphincter of Oddi dysfunction, whether emergency or not, expertise of ERCP procedure, diverticulum nearby Vater papilla, whether there was sphincterotomy or papillary balloon dilation, pancreatic duct cannulation, use of intra-ductal ultrasonography enforcement, and transpapillary biopsies had no significant differences with sPEP. CONCLUSION: Contrast media remaining in the pancreatic duct and the appearance of abdominal pain within three hours after ERCP were risk factors of sPEP.

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